STAT2, a 113 kD member of the STAT (signal transducer and activators of transcription) protein family, is phosphorylated in response to interferon alpha receptor signaling by Janus kinase I. Phosphorylation of STAT 2 induces nuclear translocation to activate transcription. STAT2 is highly expressed in the skin and thymus. STAT 2 forms complex with STAT1 and p48 to activate transcription and does not bind DNA directly. STAT 3 interacts with interferon regulatory factor 9, interferon alpha receptor, STAT 1, p48, and CREB binding protein. The Poly6245 antibody recognizes the C-terminal region of human STAT2 and has been shown to be useful for Western blotting, immunoprecipitation, and immunohistochemistry.